New Options for Knee Replacement Surgery: The Partial Knee Replacement

Arthritis: Definition, Signs and Symptoms and Diagnosis:

Arthritis, specifically osteoarthritis, affects over 23 million people in America every year. Osteoarthritis develops over a lifetime of overuse, injury, repetitive movement, or developmental disorders of the bones. When a patient has osteoarthritis of the knee, the healthy cartilage is worn away and the joint space narrows. This in turn causes pain, swelling and a decrease in movement. If the joint space narrows enough, the patient may even become bow-legged or knock-kneed. There are many treatment options available for patients with arthritis, both non-surgical and surgical.

Dr. Matthew Nadaud is a joint replacement surgeon with the Knoxville Orthopaedic Clinic and has been diagnosing and treating patients with osteoarthritis of the knee since 2001.

For patients with arthritis, a proper diagnosis is crucial in finding the best treatment options. The first step in a visit with an orthopedic surgeon is an examination. This will include a medical history, physical examination of the knee joint and x-ray examination. Cartilage cannot be seen on an x-ray, so in a normal x-ray, one sees a space between the bones in the joint. As cartilage wears away as in osteoarthritis, the space between the bones narrow or disappears altogether.

Conservative Treatments:

After the diagnosis of knee arthritis is made by an orthopedic surgeon, non-surgical treatment recommendations may include life style changes related to weight loss and exercise. Even small decreases in excess body weight can help relieve the pressure on the knee joints. Medications such as anti-inflammatories and steroid injections may help relieve both joint swelling and pain. Narcotic medications are rarely recommended for arthritis pain. If the pain becomes so unbearable that narcotics are needed, it may be time for the patient to consider joint replacement surgery.

Glucosamine (a building block of cartilage) and chondroitin sulfate (also found in cartilage) are two common supplements that may help relieve the symptoms of early osteoarthritis. You should speak with your doctor before taking any vitamins or nutritional supplements.

Support braces can also be used to straighten the leg and reduce the amount of pressure on the knee. Some patients may need a walker or a cane. Rest and ice can be used when symptoms increase.

There are many types of conservative measure for patients with arthritis of the knee. When these fail to help relieve symptoms a knee replacement may be considered.

Joint Replacement: Total Knee versus Partial Knee Replacement

Total Knee Replacement:

In a traditional total knee replacement, there is resurfacing of the damaged cartilage in all compartments of the knee where the surfaces are damaged by arthritis. (see box on arthritis). The end of the thigh bone (femur), the top of the shinbone (tibia) and the back of the knee cap (patella) are all resurfaced with metal alloy and plastic (polyethylene) components in a total knee replacement. Although, many total knee replacements are now considered MIS or minimally invasive surgery, the operation still involves extensive resurfacing of the all the cartilage in the knee. The incision is typically 4-6 inches long. A typical stay in the hospital is 3-4 days, and approximately 6-8 weeks of outpatient therapy is generally recommended. Not every person with knee arthritis needs a total knee replacement.

Partial Knee Replacement:

The partial knee replacement or unicompartmental knee replacement has demonstrated excellent outcomes for patients who meet the appropriate criteria. A partial knee replacement replaces only one side of the knee joint. Either the inside (medial) or outside (lateral) sides which demonstrate bone on bone arthritis by x-ray. Typically, knee arthritis will occur first in the inside (medial) compartment because this part of the knee bears the most weight. Therefore, the healthy portions of the knee are untouched in a partial knee replacement. There are many benefits to this procedure which may include a shorter stay in the hospital (<24 hours), a smaller incision about 3 inches long, and a faster rehabilitation compared to a total knee replacement.

Dr. Matthew Nadaud of the Knoxville Orthopaedic Clinic has been implanting partial knees for over 7 years and with great success. The Biomet Oxford® Mobile Bearing Unicompartmental Knee is designed to restore function and decrease pain for patients with osteoarthritis on the inside portion the knee. The implant has a polyethylene (plastic) bearing which is designed to glide freely throughout the knee’s range of motion. (see picture) This design more closely mimics normal knee movement. The Oxford® Partial Knee Replacement has been used in Europe for almost 20 years and was released by the FDA for use in the United States in April of 2004 with excellent clinical results.

The benefits of this particular implant include decreased or absence of poly wear (plastic), decreased incidence of implant loosening, and a knee replacement that feels more "normal."

As with all joint replacement procedures, potential complications during and after surgery include but are not limited to infection, blood clots, implant breakage and premature wear. Please speak with your surgeon about potential complications.

Recovery after partial knee replacement typically lasts half as long as traditional total knee replacement. Most patients are able to drive after two weeks, garden after three to four weeks and golf after six to eight weeks. Your surgeon will tell you when these activities and others can begin and what activities to avoid.

Specialist for Every Season

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Of the major joints of the human body, the shoulder may be the most at risk for injury. Approximately six million people in the United States visit a physician each year due to some type of shoulder problem. The shoulder moves through a greater range of motion than any other joint in the body and its amazing flexibility makes our shoulders so versatile, yet so unstable. When your shoulder is injured, your normal lifestyle suffers. Driving a car, pitching a baseball, or doing chores around the house, almost any activity requires use of the shoulder. For this reason, the rotator cuff can be damaged throughout your lifetime, sometimes to the point where surgery is needed... Learn More

Health Tips

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Business News

Welcome to Knoxville Orthopaedic Clinic’s first E-Newsletter!

We appreciate you providing us with your email address so that we might provide you with quarterly E-Newsletters that will keep you informed of what’s going on at KOC, what’s going on in our medical community and what’s going on in orthopedic medicine... Learn More